Whitney Houston, 47, voluntarily checked into an outpatient rehab program 10 days ago for drug and alcohol treatment, her rep has confirmed. Houston's first stint in rehab was in 2004 after she told Diane Sawyer in an infamous Primetime interview that she "partied a lot," but checked out only five days later. She reentered a facility a year later after her mother Cissy Houston petitioned a Georgia court to order her into rehab in March 2005.